1. Field of Invention
The present invention relates to a serial inkjet printer that has a vacuum platen for pulling the paper thereto while the recording paper is conveyed over the platen. More particularly, the invention relates to a serial inkjet printer and a printing control method for a serial inkjet printer that prevents paper dust that is propelled and made airborne by the air current produced by the vacuum action of the vacuum platen when conveying the recording paper from clinging to the ink nozzle area of the inkjet head.
2. Description of Related Art
Some inkjet printers that print to recording paper conveyed passed the printing position have a vacuum platen to prevent the recording paper from lifting away from the platen at the printing position so that the recording paper does not interfere with the inkjet head. A suction area having numerous vacuum holes is formed in the vacuum platen surface, and the recording paper conveyed over the platen surface is pulled to the platen surface by sucking air through these holes. A serial inkjet printer with such a vacuum platen is taught in Japanese Unexamined Patent Appl. Pub. JP-A-2006-248040, for example.
In order to print, this type of serial inkjet printer repeats the operations of printing to the recording paper while moving the inkjet head widthwise to the vacuum platen, and advancing the recording paper a specific pitch in the direction perpendicular to the width of the vacuum platen. This means that in order to print to the full width of the recording paper, the paper is advanced when the inkjet head is stopped near the right or left edge of the paper.
When the width of the recording paper is less than the suction area of the vacuum platen, part of the suction area is exposed outside the edges of the recording paper, and an air stream is produced around the edges of the paper by the suction of air in this exposed area. This air stream dispels chaff and dust, for example, above the edges of the recording paper.
As a result, when printing to the full width of recording paper that is narrower than the suction area of the vacuum platen, the inkjet head stops at the paper edge where chaff and dust is easily dispersed into the air. Because the paper is advanced when the inkjet head is stopped at the paper edge, the likelihood of paper dust and other dust particulate that is conveyed with the recording paper being dispersed into the air and then clinging to the ink nozzle area of the inkjet head increases. When such chaff and dust clings to the ink nozzle area of the print head, the ink nozzles can become clogged such that the ink droplets are not discharged correctly, and printing defects, such as content not being printed because ink is not discharged, can result.